John johnstons



(No Mode.)

J. JOHNSTONE.

OVEN FOR COOKING STOVBS.

N PETEns Pnaloumgnpw. wm-ngnm D.c.

, i UNITED STATEs PATENT OFFICE.

JOHN JOHNSTONE, OF DETROIT, MICHIGAN.-

OVEN FOR COOKING-STOVES.

SPECIFICATION forming part of Letters Patent No. 301,608, dated July 8,1884.

' Application {ilcd June 13, 1883. (No model.)

.To `(1J/Z whom, it may concern Be it known that I, JOHN JoHNsroNE, acitizen of the United States, residing at Detroit, in the county of"Wayne and State of Michigan, have invented a new and useful Oven forCooking-Stoves, of which the following is a specifi- `ehamberat .t m inFig. 1.

Like letters indicate `like parts in the iigures.

In the drawings, A A A representthe outer .walls or casing of a stove,which in the present example are extended at the right to formawarmingcloset, G. In the top plate, A, three holes, F, li", and F2, areshown for the reception of the usual culinary vessels. rIhe hole F2 issurrounded by a denticulated collar to permit the fumes to escape whenliquid fuel is used; but when wood, coke, or coal is used the usualstove-pipe is slipped on to connect it with a chimney.

l) is the combustionchamber, which, in the latter class of stoves, wouldbe fitted with the usual grate, draft-register, the.; but in the'present example the flames enter through the wick-cones I-I in thebottom.

M represents the casing of a door, through which the wicks are lighted.

B B B are the top, end, and bottom plates, which, with the front andback plates A and the wall of the chamber D, form the oven L.

The top plate B is extended to form the top of the hot-closet G, and thespace between the top plates A B forms the ilue l for the exit of thegaseous products of combustion.

Gis a continuous U-shaped ilue, formed by the above-described plates,andextends around.

the front or left end oi" the combustion-chamber, terminating at the topplate B.

E E E arehorizontal fines, opening a communication between the front legofthe flue O and the interiorof the oven at the top. These dues E are soshaped and placed, and in such number as to form a chimney-throat foreach wick-flame, as well as to absorb its heat and .transmit it to thecurrent of air passing into the oven through it. In thelower right endof the oven is an outlet-register, J', through which the less heated andheavier air passes out of the oven, thence along the bottom of the frontleg of the flue O to the horizontal duesE, in which it is reheated onits way into the oven again. Thus it will be seen that a continuouscirculation of heated air iskeptup through the oven, while the productsof combustion pass out directly over it.

To regulate the temperature of the oven' (which would otherwise be toohigh) a checkregister, J, is placed in the front end of the outer casingto admit cold air to the iiuesE in such volume as may be necessary.

The warming-closet G is heated indirectly that is to say, without apositive circulationthrough a register, J2, opening a communica tionwith the lower part of the right leg of the flue C, the difference indensity of the airinthe upper and lower parts of this closet beingrelied on to effect asuilicient movement through said register J 2 toaccomplish thepurpose. l As the air in the rightleg of the iue O mightbecome stagnant and merely serve as a non-con 'duct0r, I pierce afewsmall apertures th rough the top partioi' the oven-plate, therebyopening a communication with said ilue, when the circulation proceeds inthe direction of the arrows, as shown.

I am aware that open nir-iiues have been used connecting with th e spacebetween the iirebox and the oven, as shown in Patent No. 35,141, of1862. In my construction the coldair dues Vextend through the fire-boxand into the oven direct. IIn the patent referred to there is a separatechamber between the firebox and oven and between the fire-box and thesides ofthe stove, while in my device the ilues E give an extendedheating-surface directly within the drehen', and the heated air fromsuch ilues passes directly into the oven.

I deem it important that there is no connection between the oven L andthe combustionchamber. The products of combustion are checked by theform given toV the reheatinglues E E, but have a direct passage from thecombustion-chamber to the outlet over the warming-chamber.

I attach importance to the i'lues E passing IOO directly through thefire-box to give an extended heating-,surface therein, and to theirconnecting the iiues G and the open-air passages directly with theinterior of the oven. I attach importance to the voven and itscontinuous air-passages arranged entirely distinct from thecombustion-chamber and its passages, and having its independent meansfor admitting cold air directly to the reheating-iiues.

I also attach importance to thearrange-ment of the Warmingchamber G inits relation to the oven, its hot-air passages, and the means forutilizing a portion of the Waste heat from the `said oven by directingit into said Warmingchamber.

What I claim as new is l. Ina direct-draft cook-stove, and in com-fl-bination with the combustion-chamber thereg of and anoven, as L, acontinuoushot-air pasl sage distinct from the combustion-chamber, formedin part by said oven and in part by. flues extending through thefire-box to afford 1 an extended heating-surface, and mea-ns foriadmitting cold air to said air-passage, as set? forth..

2. In combination with the combus'tionchamber D, oven L, and iiues C,the heatingiues Epassing through the ire-cha-mber D to t afford anextended heating-surface Within said 3o nre-chamber, and'leadingdirectly to the oven from the flues C and from the outer air, as hereinspecified.'

3. In combination with the oven L, the coinbustion-chamber D, and thecontinuous airpassage formed in part by said oven, theheating-lues E,passing through and formed inthe structure of D to afford an extendedheatingsurface Within said fire-chamber, and connecting the oven andair-nues C, and the cold-air register leading directly to said iiues E,as

C on the same `horizontal plane, as set forth.

Joran Joiiusronn.

Witnesses:

ALLAN H. FRAZER, L. W. FRAZER.

